Localised prostate cancer was detected following a recent HOLEP operation. I am on injections, my PSA is down to 0.1 and my very enlarged prostate has shrunk to a normal size. I am about to start 4 weeks radiotherapy to eradicate any remaining cancer. I am otherwise fit and well, I run twice a week, walk the dog every day, over 10,000 steps a day.
I'm just worried about the onset of bowel dysfunction, particularly sudden urgency etc. I wonder how common this is, because I would hate to be frightened to leave the house. Any help from those who have had post-radiation effects would appreciated.
Thank you.
Hello Parkrunner
Radiotherapy is very targeted in this day and age so expect to sail through your 20 fractions.
I had my Radiotherapy in early 2023 and towards the end of the fractions the fatigue kicked in, along with the increased frequency to pee, however this went back to normal just after I had completed my 20 fractions.
it's normal before each fraction for the staff to enquire about your general health and to ask about your bowel and urinary functions and if there have been any changes, indeed every day I was given a copy of the "Bristol Stool Chart" and ask to confirm just what my last movement looked like!!
To date no post radiation side effects.
You will be fine.
Best wishes - Brian.

Macmillan Support Line - 0808 808 00 00, 7 days a week between 8am-8pm
Strength, Courage, Faith, Hope, Defiance, VICTORY.
I am a Macmillan volunteer.
Hi Parkrunner , I totally agree with Brian, RT is much more targeted than in the past. I had 37 sessions of RT over 7 years ago. It left me with slight radiation proctitis but nothing to stop me doing normal activities. Urgency has slightly increased but with a little planning isn’t an issue. The only time I have had real problems has been a couple of times after food poisoning or a bug, where I can’t control loose stools. I have seen a few cases on here where guys have had problems but by far the majority sail through RT with just fatigue and boredom!
Best wishes, David
Please remember that I am not medically trained and the above are my personal views.
Thank you. That's very reassuring as the official channels only talk about up to 50% being affected, which hopefully it is much lower.
Thank you for your prompt reply - I appreciate hearing from those affected, as the official channels tend to be less optimistic (although I suppose they have to be cautious with their advice).
Hello Parkrunner
Towards the end of RT I had some noticeable wind and mucus, but only during planned No2s. My bio also mentions one unexpected trip into the woods which I’m now convinced wasn’t due to RT, as it was very isolated and things returned to normal immediately afterwards. There may be a little more mucus now than before RT, which I don’t see as a bad thing. No urgency or other unplanned issues in the last 6 months.
You may find some of the data is based on ongoing results from earlier RT machines. I think most RT treatment now very carefully managed, controlled and focussed. I was once asked to have a walk and release some wind as it appeared the bowel size was slightly outside the tolerance line on their screen. That gave me a lot of confidence in the care being taken in their control room.
Whatever cancer throws your way, we’re right there with you.
We’re here to provide physical, financial and emotional support.
© Macmillan Cancer Support 2025 © Macmillan Cancer Support, registered charity in England and Wales (261017), Scotland (SC039907) and the Isle of Man (604). Also operating in Northern Ireland. A company limited by guarantee, registered in England and Wales company number 2400969. Isle of Man company number 4694F. Registered office: 3rd Floor, Bronze Building, The Forge, 105 Sumner Street, London, SE1 9HZ. VAT no: 668265007